I have a table that I'm trying to not only get the sum of time(hours) difference between two columns but also the amount of times a time difference is above a set amount, 6 in this case.
The total I got from Getting the sum of a datediff result but can I in the same query also get count(*) where datediff => 6?
Thanks in advance for any and all help.
DateDiff used for hours will probably not be useful, as it will return 1 hour from, say 10:55 to 11:03.
So count minutes:
Select
*, DateDiff("n", [TimeStart], [TimeEnd]) / 60 As Hours
From
YourTable
Save this query and use it as source in a new query to count those entries with an hour count greater than or equal to six:
Select Count(*) As Entries
From YourQuery
Where Hours >= 6
Related
I am trying to improve my query writing and need help with the following...
I have one table with multiple columns, including Operation_Code, Operation_Category, Downtime_In_Minutes, Downtime (as a percentage of the last 24 hours). Each line of my results set needs to SUM(Downtime_minutes) for each Operation_Code and SUM(Count of each occurrance of the Operation_Code). Stop will always be yesterday. Date functions and formatting return yesterdays date. This is not presented in the query below due to length of the code, but it works. So, each line in the results should look like:
StopDate
Operation_Code
Operation_Category
Count (# of occurrences of each Op_Code)
SUM (in minutes) of all downtime for each Operation_Code
% of Last 24 hours
Example Results:
StopDate Op_Code OP_Category Count Downtime (Minutes) % of Last 24
7/18/2021 X123 Grinder 10 720 50%
7/18/2021 A800 Cutter 12 360 25%
7/18/2021 O225 Polisher 5 60 4%
My query without attempting any aggregations is basically:
Select StopDate,
OpCode,
OpCat
From DTS
Where StopDate = yesterday
Basic question is hw do I SUM the count of occurrences and SUM the total time in minutes for each unique Operation_Code?
Thanks in advance!
Are you just looking for aggregation? Then you can use a window function to get the ratio, which I am guessing is based on the downtime:
Select StopDate, OpCode, OpCat, count(*) as cnt,
sum(Downtime_In_Minutes),
sum(Downtime_In_Minutes) * 1.0 / nullif(sum(Downtime_In_Minutes) over ()) as
From DTS
Where StopDate = yesterday;
I assume you know how to deal with "yesterday", because you say that you already have a query.
group by StopDate;
Db HIve
I'm trying to count table line each day between 8 and 9, for every day after 01-11-2020.
I would like to have data like that:
Date, count
This is the query I have tried to run and I get one line instead of a line for every single day. Could you help me with what I have done wrong?
SELECT to_date(timestamp) as dates, count(*) as Records
from table
where to_date(timestamp) > '2020-11-01' and HOUR(timestamp) BETWEEN 8 and 9
GROUP BY to_date(timestamp)
If I remove the count(*) and group by - it's run, but it is not really what I am trying to achieve.
I need to have a count(*) for each date between 8 and 9 morning, that the query would run automatically each morning and give all the data from the 01-11-2020 until the date it's run.
When I run the query just with the hour (HOUR(timestamp) BETWEEN 8 and 9) it runs correctly, but not with the entire query.
Thanks
Presumably, you don't have data on all days during that hour period. If you do have data for all days, you can tweak the query using conditional aggregation:
SELECT to_date(timestamp) as dates,
SUM(CASE WHEN HOUR(timestamp) BETWEEN 8 and 9 THEN 1 ELSE 0 END) as Records
FROM table
WHERE to_date(timestamp) > '2020-11-01' and
GROUP BY to_date(timestamp);
I have table like below:
I have to calculate daily average count of session for each user.
First i calculated, total no of sessions for each day for every user and from that i tried to calculate average of daily session. I understand that it wont work since all users dont have sessions for every date.Some dates are missing for all users. Is there any way to calculate daily average when there is no entries for some dates
WITH daily_count AS
(
SELECT user_id, to_char(local_time,’MM/DD/YYYY’) AS Date, count(session_id) AS total_count
FROM table_name
GROUP BY device_id, to_char(local_time,’MM/DD/YYYY’)
)
SELECT user_id , AVG(total_count) AS average_session_count
FROM daily_count
GROUP BY user_id
For eg: The max date in the above given table is Feb04 and the min date is Jan31 .So the total no of days is 5 days.If we take Userid 1, it is having records only for 2 dates. So the query i wrote will calculate average for 2 days not for 5 days. How to make it to calculate average for 5 days
if for date 1,2,3 number of sessions for one user is 1,0(no sessions),5 then what output do you want in average sessions? --> 2 or 3?
You need to change your main query as follows:
SELECT USER_ID,
AVG(TOTAL_COUNT) AS AVERAGE_SESSION_COUNT -- if you want output as 3 then use this
--SUM(TOTAL_COUNT)/(MAX(DATE) - MIN(DATE) + 1) -- if you want output as 2 then use this
FROM DAILY_COUNT
GROUP BY USER_ID
I'm not so expert in SQL queryes, but not even a complete newbie.
I'm exporting data from a MS-SQL database to an excel file using a SQL query.
I'm exporting many columns and two of this columns contain a date and an hour, this are the columns I use for the WHERE clause.
In detail I have about 200 rows for each day, everyone with a different hour, for many days. I need to extract the first value after the 15:00 of each day for more days.
Since the hours are different for each day i can't specify something like
SELECT a,b,hour,day FROM table WHERE hour='15:01'
because sometimes the value is at 15:01, sometimes 15:03 and so on (i'm looking for the closest value after the 15:00), for fix this i used this workaround:
SELECT TOP 1 a,b,hour,day FROM table WHERE hour > "15:00"
in this way i can take the first value after the 15:00 for a day...the problem is that i need this for more days...for a user-specifyed interval of days. At the moment i fix this with a UNION ALL statement, like this:
SELECT TOP 1 a,b,hour,day FROM table WHERE data="first_day" AND hour > "15:00"
UNION ALL SELECT TOP 1 a,b,hour,day FROM table WHERE data="second_day" AND hour > "15:00"
UNION ALL SELECT TOP 1 a,b,hour,day FROM table WHERE data="third_day" AND hour > "15:00"
...and so on for all the days (i build the SQL string with a for each day in the specifyed interval).
Until now this worked, but now I need to expand the days interval (now is maximun a week, so 5 days) to up to 60 days. I don't want to build an huge query string, but i can't imagine an alternative way for write the SQL.
Any help appreciated
Ettore
I typical solution for this uses row_number():
SELECT a, b, hour, day
FROM (SELECT t.*,
ROW_NUMBER() OVER (PARTITION BY day ORDER BY hour) as seqnum
FROM table t
WHERE hour > '15:00'
) t
WHERE seqnum = 1;
How can i calculate average of each 30 second? The following is the table structure
Price TTime
every minute 5-60 records inserted. The time is inserted by getDate(). I have to calculate average of every 30 seconds.
You need to do 2 things:
Create a column (in your SELECT result, not in the table) that contains the time in half-minutes;
calculate the average of Price using AVG(Price) and GROUP BY:
SELECT <function returning half minutes from TTime> AS HalfMinute, AVG(Price) FROM <Table> GROUP BY HalfMinute`
I don't know SQL Server's time functions. If you can get the time returned in seconds, you could go with SECONDS/30. Maybe someone else can step in with details here.
Something like:
SELECT
AVG(Price) AS AvgPrice,
COUNT(Price) AS CountPrice,
MIN(TTIME) AS PeriodBegin,
(SECOND(TTime) % 30) * 30 AS PeriodType /* either 0 or 30 */
FROM
PriceTable
GROUP BY
YEAR(TTime), MONTH(TTime), DAY(TTime), HOUR(TTime), MINUTE(TTime)
SECOND(TTime) % 30 /* either 0 or 1 */
ORDER BY
MIN(TTime)
In place of:
GROUP BY
YEAR(TTime), MONTH(TTime), DAY(TTime), HOUR(TTime), MINUTE(TTime)
you could also use, for example:
GROUP BY
LEFT(CONVERT(varchar, TTime, 120), 16)
In any case these are operation that invoke a table scan, since they are not indexable. A WHERE clause to determine the valid TTime range is advisable.
You could also make a column that contains the calculated date ('…:00.000' or '…:30.000') and fill that on INSERT with help of a trigger. Place an index on it, GROUP BY it, done.